Thanks for the answer, i dont mind uploading a screencap but literally is flying xD

First of all I took all the "dirt" around the copper
Then I started to mine below all the copper connected to the ground
After that I thought it will collapse but it didnt so I went and mine from below upwards hoping one node is supporting the rest
And lastly now I have a floating island of the first layer of copper wich dont collapse, and when I mine that part I died from fall dmg :$

its just a funny story now but a few hours ago I was tilted